Manipulating optical rotation in extraordinary transmission by hybrid plasmonic excitations

Polarized optical transmission properties through the L-shaped holes array in silver film was investigated at near infrared wavelength. Besides the enhanced transmission due to the combined plasmonic excitations, strong optical rotation was definitely observed at specific polarized incidences. After elaborate analyses, two eigenmodes were clearly characterized as the results of the hybrid localized plasmon resonances. Any polarization states from the incidences will degenerate into these two eigenstates after transmissions, suggesting a practical method to manipulate the polarization of light. Our result demonstrates the giant rotation rate achieved by the nanothin sample, indicating potential applications in the micro-optical devices. (C) 2008 American Institute of Physics.